On Reframing

There’s power in switching mental models. In my work, switching from “there might be a vulnerability in this software” to “i just haven’t found the vulnerability” was a game changer for me. I get nervous prior to presentations; one switch that helped me was that instead of thinking “my goal is to look bright” I try to remember that my goal is to teach the audience something and it doesn’t matter who stupid I look as long as they gain something from me.

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Amazing (Physical) Access Control with HID RFID cards

So my company moved to a new building which uses HID RFID cards for access control. These cards are typically white with some sort of numeric code printed on one side of them. I have not included an image of my card due to (later) obvious reasons.. Setting up my Proxmark3 RDV4 reader Some time ago I joined the Kickstarter for an updated version of the Proxmark3 RFID reader/writer and immediately broke it during the initial flash update.

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This year's review, 2018 edition

This year was good work- and health-wise, but bad when it comes to money and relationships. Financially the stock market drop hurt, emotionally getting dumped was painful. For 2019, I plan to keep and improve my healthy 2018 habits: enjoy life as non-smoker, keep on bouldering (6a+ - 6c with a rare sent 7a in-between), finally finish a full Bikram yoga sequence and maybe meditate more often. In addition, I’d like to improve my sleep.

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Wireguard vs OpenVPN on a local Gigabit Network

Wireguard is recently making a splash as human-configurable low-overhead alternative to OpenVPN and IPSec. As some privacy-centric VPN providers are planning to support it (e.g., PIA) or already have a beta running (e.g., IVPN, as tested by Ars Technica) it was time for me to look into it. The Setup To get a better feeling about the used technology I directly connected my laptop to my desktop (gigabit Ethernet with no switch/router in between) and setup OpenVPN with a minimalist configuration as well as with a more realistic TLS-configuration.

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Revising my lazy http/https interception setup

I’ve wrote about about creating a simple wireless (WLAN for us right-pondian) http/https interception setup before. Mostly I’m using this as a first step when testing mobile/desktop applications. Linux’ network-manager is perfectly able to create an software access-point with most modern network cards. Alas GNOME’s configuration tool only allows for the creation of ad-hoc networks (and switching to KDE for just this is a bit overkill for me) so you have to setup the access point on the command line with nmtui or nmcli.

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Living with changes

This year seems to bring a lot of changes: I’ve switched employers after staying on/off at a research center or the last twelve years. When I started there, I was doing cool network coding for the SECOQC quantum key distribution network, it somehow felt as being a part of some bigger undertaking that finally let to something. My work had a tenable outcome, this compensated for the long hours and poor pay.

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Fun Hacking Stuff ahead

Recently I’ve found an old post-it with guidelines I wrote myself a couple of years back, two of those stood out: make mistakes don’t buy stupid stuff Seems like I haven’t been the most consistent person back then. The post-it got discovered during a clean-up session of my flat, the same session brought up the following stupidly-bought-and-never-used gadgets: one BBC micro:bit that should be able to capture Bluetooth Low Energy transmissions one Proxmark 3 RV4 that should be able to do some nifty RFID stuff (and that I was recently able to fix) one Realtek Software-Defined Radio USB Stick (rtl-sdr).

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GnuPG/PGP and Evolution/Seahorse Private Key Woes

I have a quite simple setup: Fedora 23 on my Desktop, Ubuntu 16.04 on my Notebook and a YubiKey thrown into the mix. I do have my normal GnuPG key DD436203 that I’m using. There’s also an old and revoked key 3F5D00B6 with which I was testing my YubiKey with (note to myself: don’t use an YubiKey-crested private key as you cannot backup it). My main key offers an ElGamal 2048bit subkey – which does not work with the Yubikey (as that only supports 2048bit RSA).

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How (NOT) to hide OpenVPN behind HTTPS/SSL

Update 2017: Sadly I found out (thanks due to the comments on this blog post) that using port-share does not encapsulates subsequent traffic in normal TLS. So using this method will not fool Deep-Package Inspection Firewalls. If you need to mask all your traffic, this is not an option – you might need to investigate stunnel, information can be found here, here or here. I assume, that the higher success rate of this method could be related to some firewalls checking the target of the initial https request.

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